Atcoder Beginner Contest 284 E - Count Simple Paths Solution

   Problem Link: https://atcoder.jp/contests/abc284/tasks/abc284_e

Solution in C++:

1. /// La ilaha illellahu muhammadur rasulullah
2. ///******Bismillahir-Rahmanir-Rahim******///
3. /// Abul Hasnat Tonmoy
4. /// Department of CSE,23rd batch
5. /// Islamic University,Bangladesh
6. ///**********ALLAH IS ALMIGHTY************///
7. #include <bits/stdc++.h>
8. using namespace std;
9. int vis[200009];
10. vector<int> adj[200009];
11. int ans ;
12. void dfs( int node ){
13. if(ans==1e6)
14. return;
15. vis[node]=1;
16. ans++;
17. for ( auto v : adj[node]){
18. if(!vis[v])
19. dfs(v);
20. }
21. vis[node]=0;
22. }
23. int32_t main() {
24. int n , e ;
25. cin >> n >> e ;
26. while ( e-- ){
27. int u , v ;
28. cin >> u >> v ;
29. adj[u].push_back(v);
30. adj[v].push_back(u);
31. }
32. ans = 0 ;
33. dfs (1) ;
34. cout<<ans<<endl;
35. }